1. Field of the Invention
The present invention relates to an electrophotographic photosensitive member, a process cartridge and an electrophotographic apparatus each including the electrophotographic photosensitive member, and an imide compound.
2. Description of the Related Art
An electrophotographic photosensitive member containing an organic photoconductive substance (charge-generating substance) has been mainly used as an electrophotographic photosensitive member to be mounted onto a process cartridge or an electrophotographic apparatus. The electrophotographic photosensitive member has the following advantage. The electrophotographic photosensitive member has good film formability and can be produced by application, and hence has high productivity.
The electrophotographic photosensitive member generally includes a support and a photosensitive layer formed on the support. In addition, an undercoat layer is often formed between the support and the photosensitive layer for the purpose of suppressing the injection of charge from the support toward the photosensitive layer to suppress the occurrence of an image defect such as a black spot. A charge-generating substance having additionally high sensitivity has been used in recent years. However, as the sensitivity of the charge-generating substance rises, the amount of charge to be generated increases. Accordingly, the charge is liable to remain in the photosensitive layer and hence a positive ghost is liable to occur. The positive ghost is a phenomenon in which during the formation of one image, the density of only a portion irradiated with light at the time of forward rotation increases.
Japanese Patent Application Laid-Open No. 2007-148294 and Japanese Patent Application Laid-Open No. 2008-250082 each describe a technology involving incorporating an electron-transporting substance into the undercoat layer as a technology for suppressing such positive ghost. In addition, Japanese Patent Application Laid-Open No. 2007-148294 and Japanese Patent Application Laid-Open No. 2008-250082 each describe the following technology. When the electron-transporting substance is incorporated into the undercoat layer, the undercoat layer is cured so that the electron-transporting substance may not be eluted in a solvent in an application liquid for the photosensitive layer at the time of the formation of the layer above the undercoat layer (photosensitive layer).
A requirement for the quality of an electrophotographic image does not cease to become more and more sophisticated nowadays, and hence tolerance for the positive ghost has become markedly strict.
In addition, studies made by the inventors of the present invention have found that the technology described in each of Japanese Patent Application Laid-Open No. 2007-148294 and Japanese Patent Application Laid-Open No. 2008-250082 is still susceptible to improvement in terms of a reduction in positive ghost.